qemu/hw/virtio-scsi.c
Paolo Bonzini d2ad7dd46e virtio-scsi: add multiqueue capability
Adding multiqueue is as simple as creating more than one virtqueues,
and saving the queue number for each request.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2012-04-19 10:31:05 +02:00

630 lines
18 KiB
C

/*
* Virtio SCSI HBA
*
* Copyright IBM, Corp. 2010
* Copyright Red Hat, Inc. 2011
*
* Authors:
* Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
* Paolo Bonzini <pbonzini@redhat.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "virtio-scsi.h"
#include <hw/scsi.h>
#include <hw/scsi-defs.h>
#define VIRTIO_SCSI_VQ_SIZE 128
#define VIRTIO_SCSI_CDB_SIZE 32
#define VIRTIO_SCSI_SENSE_SIZE 96
#define VIRTIO_SCSI_MAX_CHANNEL 0
#define VIRTIO_SCSI_MAX_TARGET 255
#define VIRTIO_SCSI_MAX_LUN 16383
/* Response codes */
#define VIRTIO_SCSI_S_OK 0
#define VIRTIO_SCSI_S_OVERRUN 1
#define VIRTIO_SCSI_S_ABORTED 2
#define VIRTIO_SCSI_S_BAD_TARGET 3
#define VIRTIO_SCSI_S_RESET 4
#define VIRTIO_SCSI_S_BUSY 5
#define VIRTIO_SCSI_S_TRANSPORT_FAILURE 6
#define VIRTIO_SCSI_S_TARGET_FAILURE 7
#define VIRTIO_SCSI_S_NEXUS_FAILURE 8
#define VIRTIO_SCSI_S_FAILURE 9
#define VIRTIO_SCSI_S_FUNCTION_SUCCEEDED 10
#define VIRTIO_SCSI_S_FUNCTION_REJECTED 11
#define VIRTIO_SCSI_S_INCORRECT_LUN 12
/* Controlq type codes. */
#define VIRTIO_SCSI_T_TMF 0
#define VIRTIO_SCSI_T_AN_QUERY 1
#define VIRTIO_SCSI_T_AN_SUBSCRIBE 2
/* Valid TMF subtypes. */
#define VIRTIO_SCSI_T_TMF_ABORT_TASK 0
#define VIRTIO_SCSI_T_TMF_ABORT_TASK_SET 1
#define VIRTIO_SCSI_T_TMF_CLEAR_ACA 2
#define VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET 3
#define VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET 4
#define VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET 5
#define VIRTIO_SCSI_T_TMF_QUERY_TASK 6
#define VIRTIO_SCSI_T_TMF_QUERY_TASK_SET 7
/* Events. */
#define VIRTIO_SCSI_T_EVENTS_MISSED 0x80000000
#define VIRTIO_SCSI_T_NO_EVENT 0
#define VIRTIO_SCSI_T_TRANSPORT_RESET 1
#define VIRTIO_SCSI_T_ASYNC_NOTIFY 2
/* SCSI command request, followed by data-out */
typedef struct {
uint8_t lun[8]; /* Logical Unit Number */
uint64_t tag; /* Command identifier */
uint8_t task_attr; /* Task attribute */
uint8_t prio;
uint8_t crn;
uint8_t cdb[];
} QEMU_PACKED VirtIOSCSICmdReq;
/* Response, followed by sense data and data-in */
typedef struct {
uint32_t sense_len; /* Sense data length */
uint32_t resid; /* Residual bytes in data buffer */
uint16_t status_qualifier; /* Status qualifier */
uint8_t status; /* Command completion status */
uint8_t response; /* Response values */
uint8_t sense[];
} QEMU_PACKED VirtIOSCSICmdResp;
/* Task Management Request */
typedef struct {
uint32_t type;
uint32_t subtype;
uint8_t lun[8];
uint64_t tag;
} QEMU_PACKED VirtIOSCSICtrlTMFReq;
typedef struct {
uint8_t response;
} QEMU_PACKED VirtIOSCSICtrlTMFResp;
/* Asynchronous notification query/subscription */
typedef struct {
uint32_t type;
uint8_t lun[8];
uint32_t event_requested;
} QEMU_PACKED VirtIOSCSICtrlANReq;
typedef struct {
uint32_t event_actual;
uint8_t response;
} QEMU_PACKED VirtIOSCSICtrlANResp;
typedef struct {
uint32_t event;
uint8_t lun[8];
uint32_t reason;
} QEMU_PACKED VirtIOSCSIEvent;
typedef struct {
uint32_t num_queues;
uint32_t seg_max;
uint32_t max_sectors;
uint32_t cmd_per_lun;
uint32_t event_info_size;
uint32_t sense_size;
uint32_t cdb_size;
uint16_t max_channel;
uint16_t max_target;
uint32_t max_lun;
} QEMU_PACKED VirtIOSCSIConfig;
typedef struct {
VirtIODevice vdev;
DeviceState *qdev;
VirtIOSCSIConf *conf;
SCSIBus bus;
uint32_t sense_size;
uint32_t cdb_size;
int resetting;
VirtQueue *ctrl_vq;
VirtQueue *event_vq;
VirtQueue *cmd_vqs[0];
} VirtIOSCSI;
typedef struct VirtIOSCSIReq {
VirtIOSCSI *dev;
VirtQueue *vq;
VirtQueueElement elem;
QEMUSGList qsgl;
SCSIRequest *sreq;
union {
char *buf;
VirtIOSCSICmdReq *cmd;
VirtIOSCSICtrlTMFReq *tmf;
VirtIOSCSICtrlANReq *an;
} req;
union {
char *buf;
VirtIOSCSICmdResp *cmd;
VirtIOSCSICtrlTMFResp *tmf;
VirtIOSCSICtrlANResp *an;
VirtIOSCSIEvent *event;
} resp;
} VirtIOSCSIReq;
static inline int virtio_scsi_get_lun(uint8_t *lun)
{
return ((lun[2] << 8) | lun[3]) & 0x3FFF;
}
static inline SCSIDevice *virtio_scsi_device_find(VirtIOSCSI *s, uint8_t *lun)
{
if (lun[0] != 1) {
return NULL;
}
if (lun[2] != 0 && !(lun[2] >= 0x40 && lun[2] < 0x80)) {
return NULL;
}
return scsi_device_find(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun));
}
static void virtio_scsi_complete_req(VirtIOSCSIReq *req)
{
VirtIOSCSI *s = req->dev;
VirtQueue *vq = req->vq;
virtqueue_push(vq, &req->elem, req->qsgl.size + req->elem.in_sg[0].iov_len);
qemu_sglist_destroy(&req->qsgl);
if (req->sreq) {
req->sreq->hba_private = NULL;
scsi_req_unref(req->sreq);
}
g_free(req);
virtio_notify(&s->vdev, vq);
}
static void virtio_scsi_bad_req(void)
{
error_report("wrong size for virtio-scsi headers");
exit(1);
}
static void qemu_sgl_init_external(QEMUSGList *qsgl, struct iovec *sg,
target_phys_addr_t *addr, int num)
{
memset(qsgl, 0, sizeof(*qsgl));
while (num--) {
qemu_sglist_add(qsgl, *(addr++), (sg++)->iov_len);
}
}
static void virtio_scsi_parse_req(VirtIOSCSI *s, VirtQueue *vq,
VirtIOSCSIReq *req)
{
assert(req->elem.out_num && req->elem.in_num);
req->vq = vq;
req->dev = s;
req->sreq = NULL;
req->req.buf = req->elem.out_sg[0].iov_base;
req->resp.buf = req->elem.in_sg[0].iov_base;
if (req->elem.out_num > 1) {
qemu_sgl_init_external(&req->qsgl, &req->elem.out_sg[1],
&req->elem.out_addr[1],
req->elem.out_num - 1);
} else {
qemu_sgl_init_external(&req->qsgl, &req->elem.in_sg[1],
&req->elem.in_addr[1],
req->elem.in_num - 1);
}
}
static VirtIOSCSIReq *virtio_scsi_pop_req(VirtIOSCSI *s, VirtQueue *vq)
{
VirtIOSCSIReq *req;
req = g_malloc(sizeof(*req));
if (!virtqueue_pop(vq, &req->elem)) {
g_free(req);
return NULL;
}
virtio_scsi_parse_req(s, vq, req);
return req;
}
static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq)
{
VirtIOSCSIReq *req = sreq->hba_private;
uint32_t n = virtio_queue_get_id(req->vq) - 2;
assert(n < req->dev->conf->num_queues);
qemu_put_be32s(f, &n);
qemu_put_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
}
static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq)
{
SCSIBus *bus = sreq->bus;
VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus);
VirtIOSCSIReq *req;
uint32_t n;
req = g_malloc(sizeof(*req));
qemu_get_be32s(f, &n);
assert(n < s->conf->num_queues);
qemu_get_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem));
virtio_scsi_parse_req(s, s->cmd_vqs[n], req);
scsi_req_ref(sreq);
req->sreq = sreq;
if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
int req_mode =
(req->elem.in_num > 1 ? SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV);
assert(req->sreq->cmd.mode == req_mode);
}
return req;
}
static void virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req)
{
SCSIDevice *d = virtio_scsi_device_find(s, req->req.tmf->lun);
SCSIRequest *r, *next;
DeviceState *qdev;
int target;
/* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE". */
req->resp.tmf->response = VIRTIO_SCSI_S_OK;
switch (req->req.tmf->subtype) {
case VIRTIO_SCSI_T_TMF_ABORT_TASK:
case VIRTIO_SCSI_T_TMF_QUERY_TASK:
if (!d) {
goto fail;
}
if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
goto incorrect_lun;
}
QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
if (r->tag == req->req.tmf->tag) {
break;
}
}
if (r && r->hba_private) {
if (req->req.tmf->subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK) {
/* "If the specified command is present in the task set, then
* return a service response set to FUNCTION SUCCEEDED".
*/
req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
} else {
scsi_req_cancel(r);
}
}
break;
case VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET:
if (!d) {
goto fail;
}
if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
goto incorrect_lun;
}
s->resetting++;
qdev_reset_all(&d->qdev);
s->resetting--;
break;
case VIRTIO_SCSI_T_TMF_ABORT_TASK_SET:
case VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET:
case VIRTIO_SCSI_T_TMF_QUERY_TASK_SET:
if (!d) {
goto fail;
}
if (d->lun != virtio_scsi_get_lun(req->req.tmf->lun)) {
goto incorrect_lun;
}
QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) {
if (r->hba_private) {
if (req->req.tmf->subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK_SET) {
/* "If there is any command present in the task set, then
* return a service response set to FUNCTION SUCCEEDED".
*/
req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
break;
} else {
scsi_req_cancel(r);
}
}
}
break;
case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET:
target = req->req.tmf->lun[1];
s->resetting++;
QTAILQ_FOREACH(qdev, &s->bus.qbus.children, sibling) {
d = DO_UPCAST(SCSIDevice, qdev, qdev);
if (d->channel == 0 && d->id == target) {
qdev_reset_all(&d->qdev);
}
}
s->resetting--;
break;
case VIRTIO_SCSI_T_TMF_CLEAR_ACA:
default:
req->resp.tmf->response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
break;
}
return;
incorrect_lun:
req->resp.tmf->response = VIRTIO_SCSI_S_INCORRECT_LUN;
return;
fail:
req->resp.tmf->response = VIRTIO_SCSI_S_BAD_TARGET;
}
static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
VirtIOSCSIReq *req;
while ((req = virtio_scsi_pop_req(s, vq))) {
int out_size, in_size;
if (req->elem.out_num < 1 || req->elem.in_num < 1) {
virtio_scsi_bad_req();
continue;
}
out_size = req->elem.out_sg[0].iov_len;
in_size = req->elem.in_sg[0].iov_len;
if (req->req.tmf->type == VIRTIO_SCSI_T_TMF) {
if (out_size < sizeof(VirtIOSCSICtrlTMFReq) ||
in_size < sizeof(VirtIOSCSICtrlTMFResp)) {
virtio_scsi_bad_req();
}
virtio_scsi_do_tmf(s, req);
} else if (req->req.tmf->type == VIRTIO_SCSI_T_AN_QUERY ||
req->req.tmf->type == VIRTIO_SCSI_T_AN_SUBSCRIBE) {
if (out_size < sizeof(VirtIOSCSICtrlANReq) ||
in_size < sizeof(VirtIOSCSICtrlANResp)) {
virtio_scsi_bad_req();
}
req->resp.an->event_actual = 0;
req->resp.an->response = VIRTIO_SCSI_S_OK;
}
virtio_scsi_complete_req(req);
}
}
static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status,
size_t resid)
{
VirtIOSCSIReq *req = r->hba_private;
req->resp.cmd->response = VIRTIO_SCSI_S_OK;
req->resp.cmd->status = status;
if (req->resp.cmd->status == GOOD) {
req->resp.cmd->resid = resid;
} else {
req->resp.cmd->resid = 0;
req->resp.cmd->sense_len =
scsi_req_get_sense(r, req->resp.cmd->sense, VIRTIO_SCSI_SENSE_SIZE);
}
virtio_scsi_complete_req(req);
}
static QEMUSGList *virtio_scsi_get_sg_list(SCSIRequest *r)
{
VirtIOSCSIReq *req = r->hba_private;
return &req->qsgl;
}
static void virtio_scsi_request_cancelled(SCSIRequest *r)
{
VirtIOSCSIReq *req = r->hba_private;
if (!req) {
return;
}
if (req->dev->resetting) {
req->resp.cmd->response = VIRTIO_SCSI_S_RESET;
} else {
req->resp.cmd->response = VIRTIO_SCSI_S_ABORTED;
}
virtio_scsi_complete_req(req);
}
static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req)
{
req->resp.cmd->response = VIRTIO_SCSI_S_FAILURE;
virtio_scsi_complete_req(req);
}
static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
VirtIOSCSIReq *req;
int n;
while ((req = virtio_scsi_pop_req(s, vq))) {
SCSIDevice *d;
int out_size, in_size;
if (req->elem.out_num < 1 || req->elem.in_num < 1) {
virtio_scsi_bad_req();
}
out_size = req->elem.out_sg[0].iov_len;
in_size = req->elem.in_sg[0].iov_len;
if (out_size < sizeof(VirtIOSCSICmdReq) + s->cdb_size ||
in_size < sizeof(VirtIOSCSICmdResp) + s->sense_size) {
virtio_scsi_bad_req();
}
if (req->elem.out_num > 1 && req->elem.in_num > 1) {
virtio_scsi_fail_cmd_req(req);
continue;
}
d = virtio_scsi_device_find(s, req->req.cmd->lun);
if (!d) {
req->resp.cmd->response = VIRTIO_SCSI_S_BAD_TARGET;
virtio_scsi_complete_req(req);
continue;
}
req->sreq = scsi_req_new(d, req->req.cmd->tag,
virtio_scsi_get_lun(req->req.cmd->lun),
req->req.cmd->cdb, req);
if (req->sreq->cmd.mode != SCSI_XFER_NONE) {
int req_mode =
(req->elem.in_num > 1 ? SCSI_XFER_FROM_DEV : SCSI_XFER_TO_DEV);
if (req->sreq->cmd.mode != req_mode ||
req->sreq->cmd.xfer > req->qsgl.size) {
req->resp.cmd->response = VIRTIO_SCSI_S_OVERRUN;
virtio_scsi_complete_req(req);
continue;
}
}
n = scsi_req_enqueue(req->sreq);
if (n) {
scsi_req_continue(req->sreq);
}
}
}
static void virtio_scsi_get_config(VirtIODevice *vdev,
uint8_t *config)
{
VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
stl_raw(&scsiconf->num_queues, s->conf->num_queues);
stl_raw(&scsiconf->seg_max, 128 - 2);
stl_raw(&scsiconf->max_sectors, s->conf->max_sectors);
stl_raw(&scsiconf->cmd_per_lun, s->conf->cmd_per_lun);
stl_raw(&scsiconf->event_info_size, sizeof(VirtIOSCSIEvent));
stl_raw(&scsiconf->sense_size, s->sense_size);
stl_raw(&scsiconf->cdb_size, s->cdb_size);
stl_raw(&scsiconf->max_channel, VIRTIO_SCSI_MAX_CHANNEL);
stl_raw(&scsiconf->max_target, VIRTIO_SCSI_MAX_TARGET);
stl_raw(&scsiconf->max_lun, VIRTIO_SCSI_MAX_LUN);
}
static void virtio_scsi_set_config(VirtIODevice *vdev,
const uint8_t *config)
{
VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config;
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
if ((uint32_t) ldl_raw(&scsiconf->sense_size) >= 65536 ||
(uint32_t) ldl_raw(&scsiconf->cdb_size) >= 256) {
error_report("bad data written to virtio-scsi configuration space");
exit(1);
}
s->sense_size = ldl_raw(&scsiconf->sense_size);
s->cdb_size = ldl_raw(&scsiconf->cdb_size);
}
static uint32_t virtio_scsi_get_features(VirtIODevice *vdev,
uint32_t requested_features)
{
return requested_features;
}
static void virtio_scsi_reset(VirtIODevice *vdev)
{
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
s->sense_size = VIRTIO_SCSI_SENSE_SIZE;
s->cdb_size = VIRTIO_SCSI_CDB_SIZE;
}
/* The device does not have anything to save beyond the virtio data.
* Request data is saved with callbacks from SCSI devices.
*/
static void virtio_scsi_save(QEMUFile *f, void *opaque)
{
VirtIOSCSI *s = opaque;
virtio_save(&s->vdev, f);
}
static int virtio_scsi_load(QEMUFile *f, void *opaque, int version_id)
{
VirtIOSCSI *s = opaque;
virtio_load(&s->vdev, f);
return 0;
}
static struct SCSIBusInfo virtio_scsi_scsi_info = {
.tcq = true,
.max_channel = VIRTIO_SCSI_MAX_CHANNEL,
.max_target = VIRTIO_SCSI_MAX_TARGET,
.max_lun = VIRTIO_SCSI_MAX_LUN,
.complete = virtio_scsi_command_complete,
.cancel = virtio_scsi_request_cancelled,
.get_sg_list = virtio_scsi_get_sg_list,
.save_request = virtio_scsi_save_request,
.load_request = virtio_scsi_load_request,
};
VirtIODevice *virtio_scsi_init(DeviceState *dev, VirtIOSCSIConf *proxyconf)
{
VirtIOSCSI *s;
static int virtio_scsi_id;
size_t sz;
int i;
sz = sizeof(VirtIOSCSI) + proxyconf->num_queues * sizeof(VirtQueue *);
s = (VirtIOSCSI *)virtio_common_init("virtio-scsi", VIRTIO_ID_SCSI,
sizeof(VirtIOSCSIConfig), sz);
s->qdev = dev;
s->conf = proxyconf;
/* TODO set up vdev function pointers */
s->vdev.get_config = virtio_scsi_get_config;
s->vdev.set_config = virtio_scsi_set_config;
s->vdev.get_features = virtio_scsi_get_features;
s->vdev.reset = virtio_scsi_reset;
s->ctrl_vq = virtio_add_queue(&s->vdev, VIRTIO_SCSI_VQ_SIZE,
virtio_scsi_handle_ctrl);
s->event_vq = virtio_add_queue(&s->vdev, VIRTIO_SCSI_VQ_SIZE,
NULL);
for (i = 0; i < s->conf->num_queues; i++) {
s->cmd_vqs[i] = virtio_add_queue(&s->vdev, VIRTIO_SCSI_VQ_SIZE,
virtio_scsi_handle_cmd);
}
scsi_bus_new(&s->bus, dev, &virtio_scsi_scsi_info);
if (!dev->hotplugged) {
scsi_bus_legacy_handle_cmdline(&s->bus);
}
register_savevm(dev, "virtio-scsi", virtio_scsi_id++, 1,
virtio_scsi_save, virtio_scsi_load, s);
return &s->vdev;
}
void virtio_scsi_exit(VirtIODevice *vdev)
{
VirtIOSCSI *s = (VirtIOSCSI *)vdev;
unregister_savevm(s->qdev, "virtio-scsi", s);
virtio_cleanup(vdev);
}